The present disclosure relates to a gas turbine engine, and in particular, to a case structure therefor.
Epicyclic gearboxes with planetary or star gear trains may be used in gas turbine engines for their compact designs and efficient high gear reduction capabilities. Planetary and star gear trains generally include three gear train elements: a central sun gear, an outer ring gear with internal gear teeth, and a plurality of planet gears supported by a planet carrier between and in meshed engagement with both the sun gear and the ring gear. The gear train elements share a common longitudinal central axis, about which at least two rotate.
During flight, light weight structural cases deflect with aero and maneuver loads which may cause significant deflection commonly known as backbone bending of the engine. This deflection may result in some misalignment of the gear train elements which may lead to efficiency losses and potential reduced life. Management of the deflections of the static and rotating components as well as minimization of heat loads facilitate successful engine architectures.